In response to consumer demand and technological advances, increasingly smaller and specialized portable computing apparatuses have been designed, e.g., personal digital assistants (PDA), mobile phones, pocket computers and the like. For example, users have embraced the smaller PDAs and the like which, while designed to provide a lesser number of capabilities than personal computers (PCs), provide the most essential and used computer functions in a design which may be carried in a pocket. The specialized functions may include scheduling functions, an address database, spreadsheet applications and simple word processing or note producing applications.
The above portable computing apparatuses, which are typically referred to as digital information apparatuses, computer information appliances, etc. Many of these portable computing apparatuses combine PDA-like functions with more powerful applications, like Internet connectivity and e-mail capability. In such case, it would be desirable to have both a touch screen functionality provided by a PDA for simple tasks like retrieving a phone number or a calendar, and a convenient keyboard arrangement for other functions such as composing long e-mails, documents or the like. To the end, it would be useful to be able to quickly stow and retrieve the associated keyboard in a convenient manner.
On consideration of convenience, wireless keyboard are popularly used with portable computing apparatuses. Specifically, infrared wireless keyboards for use with portable computing apparatuses are known. An infrared wireless keyboard simply uses an infrared transmitter in the keyboard and an infrared receiver in a portable computing apparatuses to establish an link between the keyboard and the portable computing apparatus. The infrared wireless keyboard does not, of course, need a physical wire connection between the keyboard and the personal computer so that there is no wire clutter.
The infrared wireless keyboard, however, has numerous drawbacks. Specifically, the infrared wireless keyboard requires no obstacle in a path between the infrared transmitter in the keyboard and the infrared receiver in the portable computing apparatus. Whenever a portable computing apparatuses has an infrared receiver set on “odd” situation thereof, possibility of establishing transmission path between an infrared transmitter of an infrared wireless keyboard and the infrared receiver of the portable computing apparatus becomes a criterion to determine whether the wireless keyboard is available or not.
Pocketop Computer Corp. has developed an attachment for an infrared wireless keyboard used with a portable computing apparatus with an infrared receivers set on or near top side thereof. The attachment includes a support and a reflective board engaged to the support. The portable computing apparatus can be positioned substantially erected by leaning itself against the support. In such case, the reflective board can reflect infrared beam emitted from the infrared transmitter to the infrared receiver. However, it is obvious that the solution, provided by Pocketop Computer Corp., is only applied to portable computing apparatuses with infrared receivers set on or near top sides thereof. That is the wireless keyboard of the prior art is not applicable for a portable computing apparatus which has an infrared receiver set on “odd” situations thereof, e.g., waist sides or rear sides.
Gateway 2000, Inc. has utilized various improved configurations for adjusting emitting or receiving direction of an infrared emitted from or to an infrared transceiver set on an electronic apparatus. Details regarding the aforesaid improved configurations have been disclosed in the U.S. Pat. Nos. 6,104,606, 5,978,214, 5,978,213, and 5,781,405. However, it is obvious that the solutions, provided by Gateway 2000, Inc., can not be applied to compact and portable computing apparatuses equipped with infrared receivers. Even if an infrared transmitter of a wireless keyboard according to the aforesaid prior arts is capable of adjusting emitting direction of an infrared emitted therefrom, the wireless keyboard is not applicable for a portable computing apparatus which has an infrared receiver set on or near top sides thereof.
Therefore, no obstacle in the path and a shorter distance between the transmitter and the receiver constrain the flexibility that user would use a wireless keyboard because an artificial limit is placed on the location and the distance do exist between the infrared wireless keyboard and the portable computing apparatus. Moreover, the distance between the infrared wireless keyboard and the portable computing apparatus must not be too great so that the infrared receiver in the portable computing apparatus cannot detect the infrared beam from the infrared transmitter of the infrared wireless keyboard.
In addition, the infrared wireless keyboard has large power consumption requirements because of the infrared transmitter. The infrared wireless keyboard typically operates on a six-volt power source that is commonly derived from four 1.5-volt batteries. Moreover, the increased power consumption reduces overall battery life so that the batteries must be replaced more often.